In the part various procedures for the preservation of flowers and other naturally occurring materials of similar carbohydrate nature have been proposed. The basic problem is that the preservation process has usually adversely effected the appearance, shape and/or texture of the resultant treated substrate. These effects often reduced the value and esthetic appeal of the substrate.
The prior art known to applicant is as follows:
Waszkiewicz, Jr., U.S. Pat. No. 3,563,780 describes a process for preserving flowers in which a fresh flower is first dried by burying it in dry silica gel. The dried flower is then dipped in a solution of an ester-typed acrylic resin and a solvent, and air dried.
Yordan U.S. Pat. No. 3,607,488 discloses a process in which naturally occurring plant material is comminuted to a desired size and shape, e.g., one-sixteenth to one inch, treated with a preservative, e.g. aqueous "Formalin", dyed, dried and coated with a waterproof resinous sealer.
Mazzucato et al U.S. Pat. No. 3,645,766 describes a drying and storing method for flowers and leaves which are immersed in a heated powder material having a high absorbing power, so that dehydration process gradually occurs in the absence of light and active atmosphere gases, whereupon the dried flower is preheated to paraffin melting temperature and immersed for a few minutes in a melted paraffin or wax bath, then removed and cooled to room temperature.
Rovetti U.S. Pat. No. 3,861,053 described plant and related materials are dried in silica gel and borax, and the dried materials protected by coating with a solution of paraffin in an inert hydrocarbon solvent.
von Hagens U.S. Pat. Nos. 4,205,059, 4,244,992 and 4,278,701 provide a solid, substantially anhydrous body of animal or vegetal tissue and a synthetic resin substantially uniformly distributed in the tissue which is prepared from a water-bearing, normally soft tissue, normally subject to rapid decomposition and loss of weight by evaporation of its water content. The product is prepared by substantially completely removing the water content while substantially maintaining the original tissue shape and volume, uniformly impregnating the water-free tissue with a fluid precursor composition capable of being polymerized into a solid synthetic resin, and holding the impregnated tissue under polymerization conditions until the precursor composition is cured to a solid resin more rigid than the original tissue.
Fessenden U.S. Pat. No. 2,567,929 provides a process for preserving plant tissues comprising, immersing the tissues in a color stabilizing and preserving solution containing butyl alcohol, thiourea, boric acid, and ions of sodium, phosphate and borate, then allegedly dehydrating the tissues under conditions whereby their natural physical shape and stabilized color are retained, then impregnating the tissues with a solution containing hydrogenated rosin, and then applying to the impregnated tissues a coating of a vinyl chloride-acetate copolymer. This patent discloses that the butyl alcohol treatment can be carried out at 5.degree. C. for around thirty minutes which is of inadequate duration to accomplish significant dehydration of a fully intact bloom (i. e. not just petals).
The Fessenden U.S. Pat. No. 2,606,843 discloses surrounding the impregnated and/or coated material by surrounding it with a relatively thich mass of transparent, moisture-excluding, durable plastic.
The U.S. Pat. No. 2,658,836 to Fessenden shows dehydration plus impregnation with a moisture-resistant shape reinforcing substance, some of which are polymers.
Romero-Sierra U.S. Pat. No. 4,248,734 relates to a solution and process for preserving Douglas Fir needles while preventing shedding thereof from the branch to which they are naturally attached, producing a natural looking product suitable for display purposes. The branches, with attached needles, are immersed in a solution comprising water, ethyl alcohol, ethylene glycol, propionic acid, glycerin, formalin, propylene glycol, citric acid, magnesium sulphate, cupric sulphate, sodium sulphite and seaweed extract, for a period of up to about two weeks and subsequently air dried.
Romero-Sierra U.S. Pat. No. 4,272,571 describes a process for preserving substantially any variety of flower while retaining the natural colors thereof, in which the flower is immersed in an essentially water-free composition comprising: at least one dehydrating alcohol, a carboxylic acid, a urea-containing compound, an alkaline citrate, and zero to an effective amount of at leat one of a silicone fluid, a silicone resin, an alkaline formaldehyde sulfozylate, alumuminum or magnesium sulphate and cupric or other transitional metal sulphate for sufficient time to dehydrate the flower, said composition also containing a sufficient quantity of a least one compound in the group consisting of an alkaline phosphate, a lower carboxylic acid and phenol so as to ensure that the composition has a pH in the range 5-7. Following immersion the flower is dried and coated with a silicone resin.
Romero-Sierra U.S. Pat. No. 4,278,715 described a process for preserving green colored plant tissues while retaining the natural green color thereof, in which the tissues are immersed in a solution comprising: water, at least one monohydric alcohol, at least one preservative component selected from the group comprising lower carboxylic acids, di and tri hydric alcohols, and sufficient buffering and mordant reagents to control the pH and osmolality of said solution, so as to permanently retain said green color in said tissues. In a preferred embodiment the treated tissue is subjected to a secondary treatment in a holding solution comprising glycerin and water.
Romero-Sierra U.S. Pat. No. 4,328,256 describes a process for preserving green colored plant tissues and in particular coniferous needles, holly and low fiber leaves such as mosses, lichens and ferns in which selected leaves are immersed in a solution comprising water, 2-propanol, propionic acid, sulphurous acid, formalin, formic acid, ethylene glycol, and optionally minor amounts of compouns selected from the group consisting of cupric sulphate, cupricchloride, 20-20-20 fertilizer, citric acid, DBE, magnesium sulphate, acetic acid, cupric acetate, cupric nitrate, sodium phosphate, sodium sulfite, butylated hydroxytolulene and glycerol, for a sufficient time to exchange the naturally occurring water in the tissues with the "chemical water" of the solution and thereby permanently retain and biologically fix the green color of the leaves.
Japanese Patent No. 0,007,601 (1982) provides for maintaining color of cut flower used in flower arrangements by dehydrating, and immersing in grape sugar solution. It is then treated with an acetone solution containing thioures and irradiated with a high frequency electric current. The flower is treated with a treating agent consisting of dissolbed nitrated cotton, acetone and a liquid polyester, and finally dried and ornamentally arranged.
Japanese Patent No. 0,010,033 (1979) discloses living flowers and leaves which are treated and dehydrated with a water-soluble organic solvent, and impregnated with polyethylene glycol. A main stem having flowers and leaves is immersed in a solution containing N,N-dimethylformamide and the solution is gradually heated to 60 degrees C. The main stem is taken out from the solution, rinsed with methanol and immdeiately immersed in a mixed solvent of 50 parts by weight of polyethylene glycol and 50 parts by weight of methanol for 10 hours. The methanol acts as a diluent for the glycol. The stem is taken out from the mixed solvent and air dried naturally at ambient temperature over ten days.
Japanese Patent No. 0,073,501 (1984) pertains to the outer surface of a living body (e.g. vegetable, such as leaves, flowers, etc., or insects, etc.) having cuticular layer which is dried and dipped in a solution of a urethane oligomer in a solvent (e.g. methylene chloride, etc.). The body so treated is dried and then coated with a polyester paint containing a peroxide as a curing catalyst. The polyester paint may be mixed with an acrylic dental adhesive. The urethane oligomer used includes ones to be used as concrete sealants.
The Pfitzer, U.S. Pat. No. 547,227 from 1895, shows dehydration of the plants with alcohols, ethers, aldehydes, ketones, and certain hydrocarbons. It calls for the plant parts to be either dried in the open air or in the presence of hydroscopic substances. This patent also speaks of coating with shellac.
Valentine U.S. Pat. No. 1,779,299 shows preliminary treatment with alcohol and coating with a varnish or emulsion and a final coating of gelatin. The patent also, discloses adding a final waterproofing solution, which is a solution of celluloid or rubber.
The Joffe U.S. Pat. No. 2,646,512 employs salicylic acid in isopropyl alcohol in various materials.
D. A. Johansen, Science, Vol. 82, pp. 253-4, (Sept. 13, 1935), discloses what is said to be the dehydration of various plant tissues by the use of dioxane and tertiary butyl alcohol.
The dehydration efforts using lower alkanols, according to the prior art, are ineffective because the high temperatures and/or inadequate immersion and preparation results in an unacceptably distorted and unstable Free Standing Product. This invention discloses more statisfactory methods of dehydrating vegetable matter.
In contrast to the prior art, the present invention provides a chemical linkage between the dehydrated substrate and the infiltration material. Thus, in the present invention, the interstitial spaces are not simply replaced, i.e. (cell walls surrounded by another) material. Rather, the basic composition of the substrate is extended or added to, forming a continuous structure having many beneficial characteristics.
The present inventions represent a substantial advance in the this art and it is to be expected that it will be widely adopted by those skilled in the art.